面向大厚度及高强度的铁基-碳化钨梯度材料熔射成形及性能控制

Plasma spray forming is a method of direct rapid metal manufacturing and tooling，it can sharply shorten the lead-time，reduce the cost of product and shape up full-density metal die. Because a lot of factors disturb the processing of plasma spray forming, these is a long way to go to improve the precision of production. The project through the composition design and the multi-channel synchronous powder feeding inter-deposition, changes the composition and the gradient distribution and post-processing of microstructure to control the residual stress distribution and to achieve the strengthening and toughening of the deposits. Used embedded microprocessor ARM and external signal conditioning circuit as the hardware of the deposition control, and used the embedded software platform as the development of under-control software, which have a high performance in data processing and the implementation of logic function. The theoretical models of the plasma spray forming process and the characteristics of gradient coating such as its size, thickness and deposition rate are established by using acoustic emission technology for the online monitoring of crack, combined with the infrared pyrometer for the observation of bath temperature changes. The function between mainly processing parameters, such as plasma jet power, scanning speed and powder feeding rate, and laser formed structure geometry is been built. A dimensional prediction model is been built based on energy conservation principle and equation of mass conservation of laser molten-pool. Upon the completion of the project, it can provide the coagulation control of the basic theory and technology, and the theoretical basis of the plasma spray forming.

针对熔射成形零件成形精度和性能亟待提高这一关键科学问题，本项目通过成分设计和多路同步送粉交错沉积，改变成分和微结构的梯度分布实现其强韧化；基于成形机理，进一步探究等离子束加热过程中温度历史和空间的分布，分析不同加工工艺参数条件下熔射成形零件的变形规律的映射关系，推导影响等离子熔射成形结构形状的主要因素，探讨其主要工艺参数包括输出功率、送粉量和扫描速度与成形结构几何特征之间的定量关系，建立等离子熔射成形的一般工艺过程，形成等离子熔射成形结构形状预测模型，并与实际试验结果对比验证，实现预期形状结构的等离子熔射快速成形及其形状控制，提高零件成形精度和力学性能，为铁基-碳化钨梯度材料熔射成形质量控制提供理论和试验依据。

针对熔射成形零件成形精度和性能亟待提高这一关键科学问题，本项目通过成分设计和多路同步送粉交错沉积，改变成分和微结构的梯度分布实现其强韧化；基于成形机理，进一步探究等离子束加热过程中温度历史和空间的分布，分析不同加工工艺参数条件下熔射成形零件的变形规律的映射关系，推导影响等离子熔射成形结构形状的主要因素，探讨其主要工艺参数包括输出功率、送粉量和扫描速度与成形结构几何特征之间的定量关系，建立等离子熔射成形的一般工艺过程，形成等离子熔射成形结构形状预测模型，并与实际试验结果对比验证，实现预期形状结构的等离子熔射快速成形及其形状控制，提高零件成形精度和力学性能，为铁基-碳化钨梯度材料熔射成形质量控制提供理论和试验依据。